VYPER
™
VARIABLE SPEED DRIVE
INSTALLATION
S100-200 IOM (MAY 08)
Page 6
The Vyper
™
can be used at altitudes up to 10,000 ft without
derating for units without the IEEE 519 Harmonic Filter. A
Vyper
™
with the Harmonic Filter included can be operated up
to 5,000 ft without derating. Due to less dense air at higher
altitudes, the maximum entering condenser water tempera-
ture, or supply cooling water, must be reduced as shown in
the following table.
Altitude
MAX Entering
Water Temp
Vyper Coolant
Control Setpoint
0 ft 100.0°F / 37.8°C 110°F / 43.3°C
5,000 ft 95.6°F / 35.5°C 105°F / 40.5°C
10,000 ft 89.6°F / 32.0°C 100°F / 37.8°C
15,000 ft 82.3°F / 27.9°C 95°F / 35.0°C
Remotely mounted units must have the distance limited
between the Vyper
™
and the compressor motor to 50 feet
of wire or less. The problems that may be encountered with
wire lengths greater than 50 are as follows;
• VSD picks up interference in the control wiring, causing
the VSD to intermittently trip.
• Voltage drop becomes excessive, rising above the 5%
voltage drop limit.
• Peak voltage applied to the motor windings becomes
excessive and may cause premature motor failure.
• A dV/dt fi lter must be installed on remote-mounted units
with motor power lead lengths between 3 to 50 feet.
Adequate service clearances, including door swing, must
be maintained around the Vyper
™
. Care should be taken to
ensure that the Vyper
™
and it’s associated piping and wiring,
do not obstruct the access to service areas.
Liquid supply cooling temperature requirements vary be-
tween Water and Glycol cooled units. The required fl ow rate
is based on the maximum temperature of the coolant to be
used.
COOLANT TEMPERATURE LIMITS
Entering Coolant Temperature Limits (Deg F)
Min Max
Water 40 105
Glycol 35 70
General Coolant Requirements
• Vyper
™
Liquid-cooled models provide 1½ NPT threaded
connections IN and OUT of the Heat Exchanger.
• An upstream strainer is recommended to stop particulate
matter from entering the heat exchanger. The strainer
should be cleaned several times during the fi rst twenty-four
hours of operation.
• Suffi cient clearance to perform normal service and main-
tenance work should be provided around the entire unit.
• Flow rates are as shown in the chart in Figure 2.
Water Recommendations
• Johnson Controls-Frick recommends a closed-loop system
for the water side of the heat exchanger.
• We recommend a water pH level between 6.0 and 7.4 for
proper heat exchanger life.
Glycol Recommendations
• Propylene Glycol is to be used exclusively. Glycol concen-
tration must be 50% or less by volume.
Figure 2 - Flow Rates
To Next Page
Loading...
Need help?
General
